src/gmxlib/nonbonded/nb_kernel_c/nb_kernel_ElecRFCut_VdwBhamSw_GeomW3P1_c.c

   1 /*
   2  * Note: this file was generated by the Gromacs c kernel generator.
   3  *
   4  *                This source code is part of
   5  *
   6  *                 G   R   O   M   A   C   S
   7  *
   8  * Copyright (c) 2001-2012, The GROMACS Development Team
   9  *
  10  * Gromacs is a library for molecular simulation and trajectory analysis,
  11  * written by Erik Lindahl, David van der Spoel, Berk Hess, and others - for
  12  * a full list of developers and information, check out http://www.gromacs.org
  13  *
  14  * This program is free software; you can redistribute it and/or modify it under
  15  * the terms of the GNU Lesser General Public License as published by the Free
  16  * Software Foundation; either version 2 of the License, or (at your option) any
  17  * later version.
  18  *
  19  * To help fund GROMACS development, we humbly ask that you cite
  20  * the papers people have written on it - you can find them on the website.
  21  */
  22 #ifdef HAVE_CONFIG_H
  23 #include <config.h>
  24 #endif
  25
  26 #include <math.h>
  27
  28 #include "../nb_kernel.h"
  29 #include "types/simple.h"
  30 #include "vec.h"
  31 #include "nrnb.h"
  32
  33 /*
  34  * Gromacs nonbonded kernel:   nb_kernel_ElecRFCut_VdwBhamSw_GeomW3P1_VF_c
  35  * Electrostatics interaction: ReactionField
  36  * VdW interaction:            Buckingham
  37  * Geometry:                   Water3-Particle
  38  * Calculate force/pot:        PotentialAndForce
  39  */
  40 void
  41 nb_kernel_ElecRFCut_VdwBhamSw_GeomW3P1_VF_c
  42                     (t_nblist * gmx_restrict                nlist,
  43                      rvec * gmx_restrict                    xx,
  44                      rvec * gmx_restrict                    ff,
  45                      t_forcerec * gmx_restrict              fr,
  46                      t_mdatoms * gmx_restrict               mdatoms,
  47                      nb_kernel_data_t * gmx_restrict        kernel_data,
  48                      t_nrnb * gmx_restrict                  nrnb)
  49 {
  50     int              i_shift_offset,i_coord_offset,j_coord_offset;
  51     int              j_index_start,j_index_end;
  52     int              nri,inr,ggid,iidx,jidx,jnr,outeriter,inneriter;
  53     real             shX,shY,shZ,tx,ty,tz,fscal,rcutoff,rcutoff2;
  54     int              *iinr,*jindex,*jjnr,*shiftidx,*gid;
  55     real             *shiftvec,*fshift,*x,*f;
  56     int              vdwioffset0;
  57     real             ix0,iy0,iz0,fix0,fiy0,fiz0,iq0,isai0;
  58     int              vdwioffset1;
  59     real             ix1,iy1,iz1,fix1,fiy1,fiz1,iq1,isai1;
  60     int              vdwioffset2;
  61     real             ix2,iy2,iz2,fix2,fiy2,fiz2,iq2,isai2;
  62     int              vdwjidx0;
  63     real             jx0,jy0,jz0,fjx0,fjy0,fjz0,jq0,isaj0;
  64     real             dx00,dy00,dz00,rsq00,rinv00,rinvsq00,r00,qq00,c6_00,c12_00,cexp1_00,cexp2_00;
  65     real             dx10,dy10,dz10,rsq10,rinv10,rinvsq10,r10,qq10,c6_10,c12_10,cexp1_10,cexp2_10;
  66     real             dx20,dy20,dz20,rsq20,rinv20,rinvsq20,r20,qq20,c6_20,c12_20,cexp1_20,cexp2_20;
  67     real             velec,felec,velecsum,facel,crf,krf,krf2;
  68     real             *charge;
  69     int              nvdwtype;
  70     real             rinvsix,rvdw,vvdw,vvdw6,vvdw12,fvdw,fvdw6,fvdw12,vvdwsum,br,vvdwexp,sh_vdw_invrcut6;
  71     int              *vdwtype;
  72     real             *vdwparam;
  73     real             rswitch,swV3,swV4,swV5,swF2,swF3,swF4,d,d2,sw,dsw;
  74
  75     x                = xx[0];
  76     f                = ff[0];
  77
  78     nri              = nlist->nri;
  79     iinr             = nlist->iinr;
  80     jindex           = nlist->jindex;
  81     jjnr             = nlist->jjnr;
  82     shiftidx         = nlist->shift;
  83     gid              = nlist->gid;
  84     shiftvec         = fr->shift_vec[0];
  85     fshift           = fr->fshift[0];
  86     facel            = fr->epsfac;
  87     charge           = mdatoms->chargeA;
  88     krf              = fr->ic->k_rf;
  89     krf2             = krf*2.0;
  90     crf              = fr->ic->c_rf;
  91     nvdwtype         = fr->ntype;
  92     vdwparam         = fr->nbfp;
  93     vdwtype          = mdatoms->typeA;
  94
  95     /* Setup water-specific parameters */
  96     inr              = nlist->iinr[0];
  97     iq0              = facel*charge[inr+0];
  98     iq1              = facel*charge[inr+1];
  99     iq2              = facel*charge[inr+2];
 100     vdwioffset0      = 3*nvdwtype*vdwtype[inr+0];
 101
 102     /* When we use explicit cutoffs the value must be identical for elec and VdW, so use elec as an arbitrary choice */
 103     rcutoff          = fr->rcoulomb;
 104     rcutoff2         = rcutoff*rcutoff;
 105
 106     rswitch          = fr->rvdw_switch;
 107     /* Setup switch parameters */
 108     d                = rcutoff-rswitch;
 109     swV3             = -10.0/(d*d*d);
 110     swV4             =  15.0/(d*d*d*d);
 111     swV5             =  -6.0/(d*d*d*d*d);
 112     swF2             = -30.0/(d*d*d);
 113     swF3             =  60.0/(d*d*d*d);
 114     swF4             = -30.0/(d*d*d*d*d);
 115
 116     outeriter        = 0;
 117     inneriter        = 0;
 118
 119     /* Start outer loop over neighborlists */
 120     for(iidx=0; iidx<nri; iidx++)
 121     {
 122         /* Load shift vector for this list */
 123         i_shift_offset   = DIM*shiftidx[iidx];
 124         shX              = shiftvec[i_shift_offset+XX];
 125         shY              = shiftvec[i_shift_offset+YY];
 126         shZ              = shiftvec[i_shift_offset+ZZ];
 127
 128         /* Load limits for loop over neighbors */
 129         j_index_start    = jindex[iidx];
 130         j_index_end      = jindex[iidx+1];
 131
 132         /* Get outer coordinate index */
 133         inr              = iinr[iidx];
 134         i_coord_offset   = DIM*inr;
 135
 136         /* Load i particle coords and add shift vector */
 137         ix0              = shX + x[i_coord_offset+DIM*0+XX];
 138         iy0              = shY + x[i_coord_offset+DIM*0+YY];
 139         iz0              = shZ + x[i_coord_offset+DIM*0+ZZ];
 140         ix1              = shX + x[i_coord_offset+DIM*1+XX];
 141         iy1              = shY + x[i_coord_offset+DIM*1+YY];
 142         iz1              = shZ + x[i_coord_offset+DIM*1+ZZ];
 143         ix2              = shX + x[i_coord_offset+DIM*2+XX];
 144         iy2              = shY + x[i_coord_offset+DIM*2+YY];
 145         iz2              = shZ + x[i_coord_offset+DIM*2+ZZ];
 146
 147         fix0             = 0.0;
 148         fiy0             = 0.0;
 149         fiz0             = 0.0;
 150         fix1             = 0.0;
 151         fiy1             = 0.0;
 152         fiz1             = 0.0;
 153         fix2             = 0.0;
 154         fiy2             = 0.0;
 155         fiz2             = 0.0;
 156
 157         /* Reset potential sums */
 158         velecsum         = 0.0;
 159         vvdwsum          = 0.0;
 160
 161         /* Start inner kernel loop */
 162         for(jidx=j_index_start; jidx<j_index_end; jidx++)
 163         {
 164             /* Get j neighbor index, and coordinate index */
 165             jnr              = jjnr[jidx];
 166             j_coord_offset   = DIM*jnr;
 167
 168             /* load j atom coordinates */
 169             jx0              = x[j_coord_offset+DIM*0+XX];
 170             jy0              = x[j_coord_offset+DIM*0+YY];
 171             jz0              = x[j_coord_offset+DIM*0+ZZ];
 172
 173             /* Calculate displacement vector */
 174             dx00             = ix0 - jx0;
 175             dy00             = iy0 - jy0;
 176             dz00             = iz0 - jz0;
 177             dx10             = ix1 - jx0;
 178             dy10             = iy1 - jy0;
 179             dz10             = iz1 - jz0;
 180             dx20             = ix2 - jx0;
 181             dy20             = iy2 - jy0;
 182             dz20             = iz2 - jz0;
 183
 184             /* Calculate squared distance and things based on it */
 185             rsq00            = dx00*dx00+dy00*dy00+dz00*dz00;
 186             rsq10            = dx10*dx10+dy10*dy10+dz10*dz10;
 187             rsq20            = dx20*dx20+dy20*dy20+dz20*dz20;
 188
 189             rinv00           = gmx_invsqrt(rsq00);
 190             rinv10           = gmx_invsqrt(rsq10);
 191             rinv20           = gmx_invsqrt(rsq20);
 192
 193             rinvsq00         = rinv00*rinv00;
 194             rinvsq10         = rinv10*rinv10;
 195             rinvsq20         = rinv20*rinv20;
 196
 197             /* Load parameters for j particles */
 198             jq0              = charge[jnr+0];
 199             vdwjidx0         = 3*vdwtype[jnr+0];
 200
 201             /**************************
 202              * CALCULATE INTERACTIONS *
 203              **************************/
 204
 205             if (rsq00<rcutoff2)
 206             {
 207
 208             r00              = rsq00*rinv00;
 209
 210             qq00             = iq0*jq0;
 211             c6_00            = vdwparam[vdwioffset0+vdwjidx0];
 212             cexp1_00         = vdwparam[vdwioffset0+vdwjidx0+1];
 213             cexp2_00         = vdwparam[vdwioffset0+vdwjidx0+2];
 214
 215             /* REACTION-FIELD ELECTROSTATICS */
 216             velec            = qq00*(rinv00+krf*rsq00-crf);
 217             felec            = qq00*(rinv00*rinvsq00-krf2);
 218
 219             /* BUCKINGHAM DISPERSION/REPULSION */
 220             rinvsix          = rinvsq00*rinvsq00*rinvsq00;
 221             vvdw6            = c6_00*rinvsix;
 222             br               = cexp2_00*r00;
 223             vvdwexp          = cexp1_00*exp(-br);
 224             vvdw             = vvdwexp - vvdw6*(1.0/6.0);
 225             fvdw             = (br*vvdwexp-vvdw6)*rinvsq00;
 226
 227             d                = r00-rswitch;
 228             d                = (d>0.0) ? d : 0.0;
 229             d2               = d*d;
 230             sw               = 1.0+d2*d*(swV3+d*(swV4+d*swV5));
 231
 232             dsw              = d2*(swF2+d*(swF3+d*swF4));
 233
 234             /* Evaluate switch function */
 235             /* fscal'=f'/r=-(v*sw)'/r=-(v'*sw+v*dsw)/r=-v'*sw/r-v*dsw/r=fscal*sw-v*dsw/r */
 236             fvdw             = fvdw*sw - rinv00*vvdw*dsw;
 237             vvdw            *= sw;
 238
 239             /* Update potential sums from outer loop */
 240             velecsum        += velec;
 241             vvdwsum         += vvdw;
 242
 243             fscal            = felec+fvdw;
 244
 245             /* Calculate temporary vectorial force */
 246             tx               = fscal*dx00;
 247             ty               = fscal*dy00;
 248             tz               = fscal*dz00;
 249
 250             /* Update vectorial force */
 251             fix0            += tx;
 252             fiy0            += ty;
 253             fiz0            += tz;
 254             f[j_coord_offset+DIM*0+XX] -= tx;
 255             f[j_coord_offset+DIM*0+YY] -= ty;
 256             f[j_coord_offset+DIM*0+ZZ] -= tz;
 257
 258             }
 259
 260             /**************************
 261              * CALCULATE INTERACTIONS *
 262              **************************/
 263
 264             if (rsq10<rcutoff2)
 265             {
 266
 267             qq10             = iq1*jq0;
 268
 269             /* REACTION-FIELD ELECTROSTATICS */
 270             velec            = qq10*(rinv10+krf*rsq10-crf);
 271             felec            = qq10*(rinv10*rinvsq10-krf2);
 272
 273             /* Update potential sums from outer loop */
 274             velecsum        += velec;
 275
 276             fscal            = felec;
 277
 278             /* Calculate temporary vectorial force */
 279             tx               = fscal*dx10;
 280             ty               = fscal*dy10;
 281             tz               = fscal*dz10;
 282
 283             /* Update vectorial force */
 284             fix1            += tx;
 285             fiy1            += ty;
 286             fiz1            += tz;
 287             f[j_coord_offset+DIM*0+XX] -= tx;
 288             f[j_coord_offset+DIM*0+YY] -= ty;
 289             f[j_coord_offset+DIM*0+ZZ] -= tz;
 290
 291             }
 292
 293             /**************************
 294              * CALCULATE INTERACTIONS *
 295              **************************/
 296
 297             if (rsq20<rcutoff2)
 298             {
 299
 300             qq20             = iq2*jq0;
 301
 302             /* REACTION-FIELD ELECTROSTATICS */
 303             velec            = qq20*(rinv20+krf*rsq20-crf);
 304             felec            = qq20*(rinv20*rinvsq20-krf2);
 305
 306             /* Update potential sums from outer loop */
 307             velecsum        += velec;
 308
 309             fscal            = felec;
 310
 311             /* Calculate temporary vectorial force */
 312             tx               = fscal*dx20;
 313             ty               = fscal*dy20;
 314             tz               = fscal*dz20;
 315
 316             /* Update vectorial force */
 317             fix2            += tx;
 318             fiy2            += ty;
 319             fiz2            += tz;
 320             f[j_coord_offset+DIM*0+XX] -= tx;
 321             f[j_coord_offset+DIM*0+YY] -= ty;
 322             f[j_coord_offset+DIM*0+ZZ] -= tz;
 323
 324             }
 325
 326             /* Inner loop uses 153 flops */
 327         }
 328         /* End of innermost loop */
 329
 330         tx = ty = tz = 0;
 331         f[i_coord_offset+DIM*0+XX] += fix0;
 332         f[i_coord_offset+DIM*0+YY] += fiy0;
 333         f[i_coord_offset+DIM*0+ZZ] += fiz0;
 334         tx                         += fix0;
 335         ty                         += fiy0;
 336         tz                         += fiz0;
 337         f[i_coord_offset+DIM*1+XX] += fix1;
 338         f[i_coord_offset+DIM*1+YY] += fiy1;
 339         f[i_coord_offset+DIM*1+ZZ] += fiz1;
 340         tx                         += fix1;
 341         ty                         += fiy1;
 342         tz                         += fiz1;
 343         f[i_coord_offset+DIM*2+XX] += fix2;
 344         f[i_coord_offset+DIM*2+YY] += fiy2;
 345         f[i_coord_offset+DIM*2+ZZ] += fiz2;
 346         tx                         += fix2;
 347         ty                         += fiy2;
 348         tz                         += fiz2;
 349         fshift[i_shift_offset+XX]  += tx;
 350         fshift[i_shift_offset+YY]  += ty;
 351         fshift[i_shift_offset+ZZ]  += tz;
 352
 353         ggid                        = gid[iidx];
 354         /* Update potential energies */
 355         kernel_data->energygrp_elec[ggid] += velecsum;
 356         kernel_data->energygrp_vdw[ggid] += vvdwsum;
 357
 358         /* Increment number of inner iterations */
 359         inneriter                  += j_index_end - j_index_start;
 360
 361         /* Outer loop uses 32 flops */
 362     }
 363
 364     /* Increment number of outer iterations */
 365     outeriter        += nri;
 366
 367     /* Update outer/inner flops */
 368
 369     inc_nrnb(nrnb,eNR_NBKERNEL_ELEC_VDW_W3_VF,outeriter*32 + inneriter*153);
 370 }
 371 /*
 372  * Gromacs nonbonded kernel:   nb_kernel_ElecRFCut_VdwBhamSw_GeomW3P1_F_c
 373  * Electrostatics interaction: ReactionField
 374  * VdW interaction:            Buckingham
 375  * Geometry:                   Water3-Particle
 376  * Calculate force/pot:        Force
 377  */
 378 void
 379 nb_kernel_ElecRFCut_VdwBhamSw_GeomW3P1_F_c
 380                     (t_nblist * gmx_restrict                nlist,
 381                      rvec * gmx_restrict                    xx,
 382                      rvec * gmx_restrict                    ff,
 383                      t_forcerec * gmx_restrict              fr,
 384                      t_mdatoms * gmx_restrict               mdatoms,
 385                      nb_kernel_data_t * gmx_restrict        kernel_data,
 386                      t_nrnb * gmx_restrict                  nrnb)
 387 {
 388     int              i_shift_offset,i_coord_offset,j_coord_offset;
 389     int              j_index_start,j_index_end;
 390     int              nri,inr,ggid,iidx,jidx,jnr,outeriter,inneriter;
 391     real             shX,shY,shZ,tx,ty,tz,fscal,rcutoff,rcutoff2;
 392     int              *iinr,*jindex,*jjnr,*shiftidx,*gid;
 393     real             *shiftvec,*fshift,*x,*f;
 394     int              vdwioffset0;
 395     real             ix0,iy0,iz0,fix0,fiy0,fiz0,iq0,isai0;
 396     int              vdwioffset1;
 397     real             ix1,iy1,iz1,fix1,fiy1,fiz1,iq1,isai1;
 398     int              vdwioffset2;
 399     real             ix2,iy2,iz2,fix2,fiy2,fiz2,iq2,isai2;
 400     int              vdwjidx0;
 401     real             jx0,jy0,jz0,fjx0,fjy0,fjz0,jq0,isaj0;
 402     real             dx00,dy00,dz00,rsq00,rinv00,rinvsq00,r00,qq00,c6_00,c12_00,cexp1_00,cexp2_00;
 403     real             dx10,dy10,dz10,rsq10,rinv10,rinvsq10,r10,qq10,c6_10,c12_10,cexp1_10,cexp2_10;
 404     real             dx20,dy20,dz20,rsq20,rinv20,rinvsq20,r20,qq20,c6_20,c12_20,cexp1_20,cexp2_20;
 405     real             velec,felec,velecsum,facel,crf,krf,krf2;
 406     real             *charge;
 407     int              nvdwtype;
 408     real             rinvsix,rvdw,vvdw,vvdw6,vvdw12,fvdw,fvdw6,fvdw12,vvdwsum,br,vvdwexp,sh_vdw_invrcut6;
 409     int              *vdwtype;
 410     real             *vdwparam;
 411     real             rswitch,swV3,swV4,swV5,swF2,swF3,swF4,d,d2,sw,dsw;
 412
 413     x                = xx[0];
 414     f                = ff[0];
 415
 416     nri              = nlist->nri;
 417     iinr             = nlist->iinr;
 418     jindex           = nlist->jindex;
 419     jjnr             = nlist->jjnr;
 420     shiftidx         = nlist->shift;
 421     gid              = nlist->gid;
 422     shiftvec         = fr->shift_vec[0];
 423     fshift           = fr->fshift[0];
 424     facel            = fr->epsfac;
 425     charge           = mdatoms->chargeA;
 426     krf              = fr->ic->k_rf;
 427     krf2             = krf*2.0;
 428     crf              = fr->ic->c_rf;
 429     nvdwtype         = fr->ntype;
 430     vdwparam         = fr->nbfp;
 431     vdwtype          = mdatoms->typeA;
 432
 433     /* Setup water-specific parameters */
 434     inr              = nlist->iinr[0];
 435     iq0              = facel*charge[inr+0];
 436     iq1              = facel*charge[inr+1];
 437     iq2              = facel*charge[inr+2];
 438     vdwioffset0      = 3*nvdwtype*vdwtype[inr+0];
 439
 440     /* When we use explicit cutoffs the value must be identical for elec and VdW, so use elec as an arbitrary choice */
 441     rcutoff          = fr->rcoulomb;
 442     rcutoff2         = rcutoff*rcutoff;
 443
 444     rswitch          = fr->rvdw_switch;
 445     /* Setup switch parameters */
 446     d                = rcutoff-rswitch;
 447     swV3             = -10.0/(d*d*d);
 448     swV4             =  15.0/(d*d*d*d);
 449     swV5             =  -6.0/(d*d*d*d*d);
 450     swF2             = -30.0/(d*d*d);
 451     swF3             =  60.0/(d*d*d*d);
 452     swF4             = -30.0/(d*d*d*d*d);
 453
 454     outeriter        = 0;
 455     inneriter        = 0;
 456
 457     /* Start outer loop over neighborlists */
 458     for(iidx=0; iidx<nri; iidx++)
 459     {
 460         /* Load shift vector for this list */
 461         i_shift_offset   = DIM*shiftidx[iidx];
 462         shX              = shiftvec[i_shift_offset+XX];
 463         shY              = shiftvec[i_shift_offset+YY];
 464         shZ              = shiftvec[i_shift_offset+ZZ];
 465
 466         /* Load limits for loop over neighbors */
 467         j_index_start    = jindex[iidx];
 468         j_index_end      = jindex[iidx+1];
 469
 470         /* Get outer coordinate index */
 471         inr              = iinr[iidx];
 472         i_coord_offset   = DIM*inr;
 473
 474         /* Load i particle coords and add shift vector */
 475         ix0              = shX + x[i_coord_offset+DIM*0+XX];
 476         iy0              = shY + x[i_coord_offset+DIM*0+YY];
 477         iz0              = shZ + x[i_coord_offset+DIM*0+ZZ];
 478         ix1              = shX + x[i_coord_offset+DIM*1+XX];
 479         iy1              = shY + x[i_coord_offset+DIM*1+YY];
 480         iz1              = shZ + x[i_coord_offset+DIM*1+ZZ];
 481         ix2              = shX + x[i_coord_offset+DIM*2+XX];
 482         iy2              = shY + x[i_coord_offset+DIM*2+YY];
 483         iz2              = shZ + x[i_coord_offset+DIM*2+ZZ];
 484
 485         fix0             = 0.0;
 486         fiy0             = 0.0;
 487         fiz0             = 0.0;
 488         fix1             = 0.0;
 489         fiy1             = 0.0;
 490         fiz1             = 0.0;
 491         fix2             = 0.0;
 492         fiy2             = 0.0;
 493         fiz2             = 0.0;
 494
 495         /* Start inner kernel loop */
 496         for(jidx=j_index_start; jidx<j_index_end; jidx++)
 497         {
 498             /* Get j neighbor index, and coordinate index */
 499             jnr              = jjnr[jidx];
 500             j_coord_offset   = DIM*jnr;
 501
 502             /* load j atom coordinates */
 503             jx0              = x[j_coord_offset+DIM*0+XX];
 504             jy0              = x[j_coord_offset+DIM*0+YY];
 505             jz0              = x[j_coord_offset+DIM*0+ZZ];
 506
 507             /* Calculate displacement vector */
 508             dx00             = ix0 - jx0;
 509             dy00             = iy0 - jy0;
 510             dz00             = iz0 - jz0;
 511             dx10             = ix1 - jx0;
 512             dy10             = iy1 - jy0;
 513             dz10             = iz1 - jz0;
 514             dx20             = ix2 - jx0;
 515             dy20             = iy2 - jy0;
 516             dz20             = iz2 - jz0;
 517
 518             /* Calculate squared distance and things based on it */
 519             rsq00            = dx00*dx00+dy00*dy00+dz00*dz00;
 520             rsq10            = dx10*dx10+dy10*dy10+dz10*dz10;
 521             rsq20            = dx20*dx20+dy20*dy20+dz20*dz20;
 522
 523             rinv00           = gmx_invsqrt(rsq00);
 524             rinv10           = gmx_invsqrt(rsq10);
 525             rinv20           = gmx_invsqrt(rsq20);
 526
 527             rinvsq00         = rinv00*rinv00;
 528             rinvsq10         = rinv10*rinv10;
 529             rinvsq20         = rinv20*rinv20;
 530
 531             /* Load parameters for j particles */
 532             jq0              = charge[jnr+0];
 533             vdwjidx0         = 3*vdwtype[jnr+0];
 534
 535             /**************************
 536              * CALCULATE INTERACTIONS *
 537              **************************/
 538
 539             if (rsq00<rcutoff2)
 540             {
 541
 542             r00              = rsq00*rinv00;
 543
 544             qq00             = iq0*jq0;
 545             c6_00            = vdwparam[vdwioffset0+vdwjidx0];
 546             cexp1_00         = vdwparam[vdwioffset0+vdwjidx0+1];
 547             cexp2_00         = vdwparam[vdwioffset0+vdwjidx0+2];
 548
 549             /* REACTION-FIELD ELECTROSTATICS */
 550             felec            = qq00*(rinv00*rinvsq00-krf2);
 551
 552             /* BUCKINGHAM DISPERSION/REPULSION */
 553             rinvsix          = rinvsq00*rinvsq00*rinvsq00;
 554             vvdw6            = c6_00*rinvsix;
 555             br               = cexp2_00*r00;
 556             vvdwexp          = cexp1_00*exp(-br);
 557             vvdw             = vvdwexp - vvdw6*(1.0/6.0);
 558             fvdw             = (br*vvdwexp-vvdw6)*rinvsq00;
 559
 560             d                = r00-rswitch;
 561             d                = (d>0.0) ? d : 0.0;
 562             d2               = d*d;
 563             sw               = 1.0+d2*d*(swV3+d*(swV4+d*swV5));
 564
 565             dsw              = d2*(swF2+d*(swF3+d*swF4));
 566
 567             /* Evaluate switch function */
 568             /* fscal'=f'/r=-(v*sw)'/r=-(v'*sw+v*dsw)/r=-v'*sw/r-v*dsw/r=fscal*sw-v*dsw/r */
 569             fvdw             = fvdw*sw - rinv00*vvdw*dsw;
 570
 571             fscal            = felec+fvdw;
 572
 573             /* Calculate temporary vectorial force */
 574             tx               = fscal*dx00;
 575             ty               = fscal*dy00;
 576             tz               = fscal*dz00;
 577
 578             /* Update vectorial force */
 579             fix0            += tx;
 580             fiy0            += ty;
 581             fiz0            += tz;
 582             f[j_coord_offset+DIM*0+XX] -= tx;
 583             f[j_coord_offset+DIM*0+YY] -= ty;
 584             f[j_coord_offset+DIM*0+ZZ] -= tz;
 585
 586             }
 587
 588             /**************************
 589              * CALCULATE INTERACTIONS *
 590              **************************/
 591
 592             if (rsq10<rcutoff2)
 593             {
 594
 595             qq10             = iq1*jq0;
 596
 597             /* REACTION-FIELD ELECTROSTATICS */
 598             felec            = qq10*(rinv10*rinvsq10-krf2);
 599
 600             fscal            = felec;
 601
 602             /* Calculate temporary vectorial force */
 603             tx               = fscal*dx10;
 604             ty               = fscal*dy10;
 605             tz               = fscal*dz10;
 606
 607             /* Update vectorial force */
 608             fix1            += tx;
 609             fiy1            += ty;
 610             fiz1            += tz;
 611             f[j_coord_offset+DIM*0+XX] -= tx;
 612             f[j_coord_offset+DIM*0+YY] -= ty;
 613             f[j_coord_offset+DIM*0+ZZ] -= tz;
 614
 615             }
 616
 617             /**************************
 618              * CALCULATE INTERACTIONS *
 619              **************************/
 620
 621             if (rsq20<rcutoff2)
 622             {
 623
 624             qq20             = iq2*jq0;
 625
 626             /* REACTION-FIELD ELECTROSTATICS */
 627             felec            = qq20*(rinv20*rinvsq20-krf2);
 628
 629             fscal            = felec;
 630
 631             /* Calculate temporary vectorial force */
 632             tx               = fscal*dx20;
 633             ty               = fscal*dy20;
 634             tz               = fscal*dz20;
 635
 636             /* Update vectorial force */
 637             fix2            += tx;
 638             fiy2            += ty;
 639             fiz2            += tz;
 640             f[j_coord_offset+DIM*0+XX] -= tx;
 641             f[j_coord_offset+DIM*0+YY] -= ty;
 642             f[j_coord_offset+DIM*0+ZZ] -= tz;
 643
 644             }
 645
 646             /* Inner loop uses 136 flops */
 647         }
 648         /* End of innermost loop */
 649
 650         tx = ty = tz = 0;
 651         f[i_coord_offset+DIM*0+XX] += fix0;
 652         f[i_coord_offset+DIM*0+YY] += fiy0;
 653         f[i_coord_offset+DIM*0+ZZ] += fiz0;
 654         tx                         += fix0;
 655         ty                         += fiy0;
 656         tz                         += fiz0;
 657         f[i_coord_offset+DIM*1+XX] += fix1;
 658         f[i_coord_offset+DIM*1+YY] += fiy1;
 659         f[i_coord_offset+DIM*1+ZZ] += fiz1;
 660         tx                         += fix1;
 661         ty                         += fiy1;
 662         tz                         += fiz1;
 663         f[i_coord_offset+DIM*2+XX] += fix2;
 664         f[i_coord_offset+DIM*2+YY] += fiy2;
 665         f[i_coord_offset+DIM*2+ZZ] += fiz2;
 666         tx                         += fix2;
 667         ty                         += fiy2;
 668         tz                         += fiz2;
 669         fshift[i_shift_offset+XX]  += tx;
 670         fshift[i_shift_offset+YY]  += ty;
 671         fshift[i_shift_offset+ZZ]  += tz;
 672
 673         /* Increment number of inner iterations */
 674         inneriter                  += j_index_end - j_index_start;
 675
 676         /* Outer loop uses 30 flops */
 677     }
 678
 679     /* Increment number of outer iterations */
 680     outeriter        += nri;
 681
 682     /* Update outer/inner flops */
 683
 684     inc_nrnb(nrnb,eNR_NBKERNEL_ELEC_VDW_W3_F,outeriter*30 + inneriter*136);
 685 }